slurm priority support (#419)

Author: sharabiani

src/xpk/core/kjob.py

@@ -86,6 +86,7 @@ class PodTemplateDefaults(Enum):
               workingDir: {working_directory}
               {resources}
           {node_selector}
+          priorityClassName: {priority}
           restartPolicy: OnFailure
           serviceAccountName: {service_account}
 """
@@ -286,6 +287,7 @@ def create_job_template_instance(
       working_directory=working_directory,
       resources=resources,
       node_selector=node_selector,
+      priority=args.priority if hasattr(args, "priority") else "medium",
       service_account=service_account,
   )
   if system is not None and system.accelerator_type == AcceleratorType["GPU"]:

src/xpk/parser/common.py

@@ -247,3 +247,13 @@ def add_slurm_arguments(custom_parser: argparse.ArgumentParser):
           'and "days-hours:minutes:seconds".'
       ),
   )
+  custom_parser.add_argument(
+      '--priority',
+      type=str,
+      default='medium',
+      choices=['very-low', 'low', 'medium', 'high', 'very-high'],
+      help=(
+          'A priority, one of `very-low`, `low`, `medium`, `high` or'
+          ' `very-high`. Defaults to `medium`.'
+      ),
+  )